Study and analysis of factors determining a process of bioreceptor layer formation on a surface of AU contacts in biosensors detecting pathogens in aquaculture

Sensors are becoming increasingly important every day, especially in applications such ashealthcare, medical and veterinary diagnostics, and food quality control, the safety of which is becominga more important issue worldwide. The present study investigated the critical aspects of the formationof the bioreceptor layer on biosensors and their impedance response for use in pathogen detectionin aquaculture. As a result of the studies, conducted with gold substrates of different roughness,a correlation was observed between the degree of development of the Au electrode surfaces andformation of the correct bioreceptor layer. These changes were observed on the basis of a wetting angleanalysis for selected substrates. Measurements using electrochemical impedance spectroscopy showedthat gold electrodes with lower substrate roughness obtained a better impedance response (Nyquistplot). On the basis of a comprehensive analysis of the results, an innovative criterion was developedto evaluate the quality of biosensors at an early stage of their production.Keywords: gold substrate, Electrochemical Impedance Spectroscopy, Biosensors, pathogen detection